Vehicle for sweeping large surfaces



Feb. 15, 1966 J. E. LYON 3,234,576

VEHICLE FOR SWEEPING LARGE SURFACES Original Filed Dec. 28, 1961 5 Sheets-Sheet 1 INVENTOR. JAMES E. LYON @MQM AT TORNEYS Feb. 15, 1966 J, LYON 3,234,576

VEHICLE FOR SWEEPING LARGE SURFACES Original Filed Dec. 28, 1961 3 Sheets-Sheet 2 FIG. 3

TNVENTOR.

JAMES E. LYON BY @m 'aua ATTORNEYS Feb. 15, 1966 J. E. LYON 3,234,576

VEHICLE FOR SWEEPING LARGE SURFACES Original Filed Dec. 28, 1961 3 Sheets-Sheet 5 v INVENTOR. JAMES E. LYON ATTORNEYS United States Patent Ofiice 3,234,576 Patented Feb. 15, 1966 3,234,576 VEHICLE FOR SWEEPING LARGE SURFACES James E. Lyon, Perrysburg, Ohio, assignor to American lihncoln Corporation, Toledo, Ohio, a corporation of Original application Dec. 28, 1961, Ser. No. 162,674. Divided and this application July 27, 1964, Ser. No. 395,631

8 Claims. (Cl. 82)

This is a division of application Serial No. 162,674, filed December 28, 1961.

This invention relates to an improved power sweeper and more particularly to a power sweeper of the riding type which is especially designed to sweep factory and institutional floors and similar large surfaces.

Sweepers of the general type with which the present invention is concerned are known in the art. Most of these sweepers have a large cylindrical broom which is rotated in contact with a surface to be swept on an axis which is parallel to the surface and perpendicular to the movement of the machine. Frequently, the sweepers have a side broom located to one side and in front of the sweeper to facilitate cleaning areas adjacent walls, curbs, or the like. However, such sweepers have had a number of shortcomings which the sweeper according to the present invention overcomes.

In previously known sweepers of the type in which the main broom sweeps the dirt in an are into a hopper located therebehind, flaps are located in front of the brooms and in contact with the surface to prevent dirt from being thrown outwardly in front of the sweepers during rotation of the brooms. Such flaps have been made of thin, yieldable material to enable most dirt to pass easily underneath as the sweepers move along. However, larger and particularly lighter debris frequently is trapped by the flaps and moved along with the sweeper. To release such trapped debris, sweepers heretofore known have been provided with means for raising the flaps. In some instances, the flap itself has been lineally raised and lowered in a given path whereas in other cases the entire sweeper body has been hinged in a central portion and jackknifed so that the entire central part of the body is raised along with the flap. While these approaches have been effective in most instances, if the flap does not clear the debris, or if the debris is caught between the sweeper and the surface near the flap, it will not be released but will continue to be carried along under the machine.

The flap of the new sweeper is raised and lowered to release debris but moves in an arcuate path so that the lower edge of the flap swings downwardly in front of its original position whereby any debris caught under or near the flap is pushed rearwardly as the flap is raised and lowered. The flap thus establishes a positive force for pushing the debris rearwardly and thus releases the debris even though it is caught under the sweeper and ordinarily would not be completely cleared when the flap is raised. This is also accomplished without the necessity of jackknifing the entire sweeper body.

The new sweeper has improved mechanism for raising and lowering the main broom to place it in contact with the floor during the sweeping operation and to raise it out of the way when not needed. The new mechanism also provides an effective adjustment for changing the pressure on the broom as well as enabling a temporary increase in pressure thereon to enable more sweeping power in recesses and the like and to remove sticky or similar debris requiring more pressure in order to be picked up by the broom. The main broom mechanism also cooperates with the mechanism for raising and lowering the front flap in a manner such that the main broom and flap can be raised and lowered together, if desired. This simplifies the operation and keeps the number of operator controls to a minimum.

It is, therefore, a principal object of the invention to provide an improved power sweeper.

Another object of the invention is to provide a power sweeper which is capable of cleaning surfaces, and particularly uneven surfaces, more effectively than heretofore.

Still another object of the invention is to provide a power sweeper with less complicated controls which are easier to operate.

Yet another object of the invention is to provide a power sweeper which is capable of disposing of larger debris without trapping and dragging the debris along with the sweeper.

A further object of the invention is to provide a sweeper with a front flap capable of feeding trapped debris rearwardly thereof.

Many other objects and advantages of the invention will be apparent from the following detailed description of a preferred embodiment thereof, reference being made to the accompanying drawings, in which:

FIG. 1 is an overall view in perspective of a ridingtype power sweeper embodying the principle-s of the present invention;

FIG. 2 is a fragmentary side view in elevation of a main broom and a front flap of the sweeper shown in FIG. 1, the front flap being sectioned;

FIG. 3 is an enlarged, fragmentary, side view of the main broom and front flap shown in FIG. 2, with the front flap in a raised position;

FIG. 4 is a view in perspective of the main broom of the sweeper shown in FIG. 1, with mechanism for raising and lowering the broom and for varying the pressure thereon, and with means for raising and lowering the front flap of FIGS. 2 and 3;

FIG. 5 is an enlarged, detailed side view in elevation of a portion of the controls shown in FIG. 4.

Referring to the drawings, and more particularly to FIG. 1, an overall power sweeping machine embodying the principles of the present invention is indicated by the numeral 20. The sweeper 20 includes a main frame or body 22 supported on a pair of driven, rear wheels 24 and a single, centrally located front wheel 26. The front wheel 26 is steered through suitable mechanism associated with a steering wheel 28 located in front of an operators seat 30.

The sweeper 20 also includes a pair of headlights 32 which are particularly useful when factory aisles and similar other dark areas are being cleaned, the headlights 32 being mounted on an operators panel 34. The panel 34 is supported on a deck 36 which constitutes part of the frame 22 with suitable foot controls being located just above the deck 36 behind the panel 34 for controlling the drive for the rear wheels 24 and also for stopping the sweeper. These controls can be of any suitable design, as is known in the art, and will not be discussed in any detail. To one side of the operators seat 30 is a control board generally indicated at 38 containing a plurality of levers for controlling various elements of the sweeper 20 including the wheel transmission.

A side broom 40 is located under the front, right corner of the sweeper 20, this broom enabling the sweeper to clean closely to a wall or curb, for example, with the broom 40 sweeping the dirt toward the center of the sweeper 20. The sweeper can also be supplied with a similar side broom at the front, left corner, if desired.

The dirt swept to the center of the sweeper 20 by the broom 40, as well as other dirt passing under the sweeper 20, passes under a front flap 42 and is picked up by a main broom 44. The main broom 44 carries this dirt into a hopper-46in which heavier dirt and debris is deposited, with-lighter dirt particles being eventually passed through a plurality of filter bags 48 which collect the remaining dirt and allow the air to pass to the atmosphere. The

dirt collected:in the filter bags-.48'can then be separated broom. 44=with-theuaid-of thefrontflap 42 and side flaps along with a rear flap 143 (FIG. 1) to confine dust-stirred up by the: broom 44;v AIlof-the dirt sweptby the main broom 44rmust first pass under the front flap 42 and for thisreason the flap includes a first strip;144- (FIGS. 2 and 3) of thin, flexible material under which most-debris can easily pass However; larger and lighter debris, such as a'wad of paper shown in FIG. 3, will occasionally be dragged along by the flap 42 instead of passingthereunder and being 1 swept up by the main-broom 44; When this happens, the flap 42 can be raisedand-lowered in a manner which not onlyusually releases the debris but, vwhen released, actually forces the: debris rearwardly toward the broom 44.

Thefront flap 42 includes, besides the thin, Wide strip 144, a second, stiffer and narrower strip 146 which enables better control oflthe stripj144- and can also help move debris under the flap 42; aslwill be more apparent subsequently. The strips 144-and 1'46 are'afiixed between'a front flap axle or supporting bar 148 and a mounting flange 150 withithe width of the strip144-being greater than the distance from the axle 148 to the surface being 20. The backing strip 152.contactsthethin strip 144. at

an-intermediate point and limits the rearward movement of the thin strip 144't0 prevent-it from possibly catching in the main broom 44. The back-ingflap 152 also lessens the chance that dirt will be kicked out; in front of the main broom 44-when the front-flap 42 is raised.

Should'a-larger piece of debris now be caught between the surface and the front flap 42 and be dragged along by the sweeper; it usually can be passed back to the broom 44 simply by raising the flap 42. For this purpose, a front flap; cable 156 is-provided-which can be pulledand released by the operator by any suitable means. The cable 156 in this instance wraps around a suitable idler 158 and is wrapped at least once around one end of the axle 148, being affixed to an annular flange 160 of the axle 148 by being passed through holes 162 therein. The cable continues past the axle 148 where it is-fastened to a cable spring 164, the opposite end of which is suitably affixed to the frame 22. When the cable is raised, it rotates the axle 148 in a counterclockwise direction, causing the front flap 42 to raise toan upper position, as shown in FIG. 3. The axle 148 partially rolls up the strip 144 similarly to a window'shade sothat it first pulls the strip 144-upwardly when moving it from beneath the backing strip 152, before swinging it forwardly. At this time, the spring 164 is placed-in tension so that when the cable is again released, the spring will cause: the flap 42 to return to the original position, as shown in FIG. 2. It will be noted that when the flap 42 israised and lowered rapidly, the lower end of the thin strip 144' descends through a path in front of its upward path and contacts the surface well in front of the previous point of contact therewith. Hence, the strip 144'will usually contact the surface in front of the debris which was'previously trapped and thus enable it to move rearwardly toward the main broom 44, with the thin strip 144 event lly assuming the original position as shown in FIG. 2 again, when the sweeper 20'is moving forwardly. It will be readily seen that by swinging down in front of the debris previously trapped,

the flap 42 has maximum effectiveness in releasing the debris and in pushing it toward the rear.

If even larger debris. is encountered, as a milk carton, for example, the thin strip 144 will not always clear it and release it to them-ain broom 44. In such an instance, the heavier strip 146 takes over and moves the larger debris rearwardly. The heavier strip 146 moves in the same general manner as the strip 144 when the flap 42 is raised and lowered. When the strip 146 is raised and lowered, the outer edge thereof moves in an arcuate path and, when being lowered, pushes rearwardly any debris encountered. Hence, by several successive upward and downward movements of. the flap. 42, the-strip 146 will push the debris rearwardly in successive steps, even causing the backing strip. 152 to yield during, such movement, if necessary. However, the strip 1.46v goes even further than this in that itwill crush or squeeze many of the larger pieces encountered to a smaller and more handleable size.

Thus, it will be seen that the front flap 42', with its arcuate raising and lowering motion, is extremely important in minimizing the chance. that debris can be caught under the sweeper 20' and pushed uselessly therealong. The thin strip 144 of the flap 42' can be swung in front of most debris to assure the rearward movement thereof while the heavier, narrower strip. 146 actually pushes the larger debris rearwardly during the arcuate lowering movement thereof and can even squeeze or crush some of the larger debris.

Referring to FIGS. 4 and 5, the cable 156 can be coupled with the controls for the main broom 44. Accordingly, the cable 156 is affixed to a cable arm 166 which in turn is aflixed to a cable shaft 168 whichextends transversely of .the sweeper 20 and is suitably supported by suitable bearing, blocks 170and 172 on portions of the frame 22. The opposite end of the shaft 168' is affixed to an upwardly extendingroller arm 174'at. the upper end of which is rotatably mounted .a roller 176. Theroller 176 cooperates with a cam plate 178 which is pivoted by a pin 180 and is moved in either a downward, clockwise direction or an upward, counterclockwise direction by a front flap handle 182. Whether the handle 182 is manipulated to move the cam plate 178 in either direction, the arm 174 will be forced downwardly or in a clockwise direction and, through the shaft 168, similarly move the arm 166 in a clockwise direction. This will move the upper end of the cable 156 toward the rear of the sweeper 20 and thus raise the front flap 42 in the manner previously discussed. Hence, the front flapwill be raised whether the handle 182 is moved .up or'down,

The main broom 44 has a central axle 184 rotatably supported at one end by a generally T-shape, axle-supporting member 186 which is rotatably supported at its other end on a driven shaft 821 The opposite end of the axle 184 has a main broom driven sprocket 188 which rotates the axle 184 by means of a chain 190 and a main broom, drive sprocket 192, the latter being mounted on the driven shaft 82' which is driven by a drive sheave 106 powered by a motor 108 (FIG. l). A heavy chain guard 194 extends around the sprockets 188'and 192' and the chain 190 and is-rotatably connected to the axle 184 with its opposite end rotatably supported on the driven shaft 82. With this arrangement, the main broom 44 can pivot about the driven shaft 82 by means of the T-shaped members 186 and the chain guard 194. The T -shaped member 186 is connected'by a lift rod 196 to a lift arm 198 which is affixed to a lift shaft 200, while the heavy guard 194 is similary affixed to a second lift rod 202 which is connected to a secondlift arm 204 which is afiixed to the lift shaft 200. When the lift shaft 200 is rotated in a counterclock-. wise direction, it raises both of the rods 196 and 202 and, hence, the main broom 44 as a unit.

A generally triangular-shaped lift plate 206 is afiixedj to a central portion of the lift shaft 200 and has a main broom handle 208 for moving the plate 206. When the handle 208 is moved upwardly, the lift arms 198 and 204 are similarly lifted to raise the broom 44. Similarly, if the handle 208 is pushed downwardly, the arms 198 and 204 also urge the broom 44 downwardly so that the pressure of the broom 44 on the surface being swept will be increased. This is extremely advantageous in the sweeping operation because the pressure can be temporarily decreased or increased to meet certain needs. Thus, the broom can be raised temporarily when the sweeper runs over a doorsill, for example. Also, the pressure can be increased to remove certain diflicult substances from the floor, for example. It also enables recesses to be swept more thoroughly than otherwise.

Close regulation of the average pressure of the broom 44 on the surface is quite important and can be controlled by three pressure springs 210, one end of each being fixed to a portion of the main frame 22 and the other end of each being connected to a rectangular adjusting member 212. The rectangular member 212 is adjustably attached to a pin or bolt 214 at the upper end of the triangular plate 206, the bolt 214 extending through the member 212 and engaging a head 216 of an adjusting bolt 218. With this arrangement, when the bolt 218 is screwed inwardly or outwardly, it changes the position of the rectangular member 212 relative to the bolt 214 and thereby changes the tension on the springs 210. The springs 210, being under tension, urge the plate 206 in a counterclockwise direction as to urge the arms 198 and 204 upwardly along with the main broom 44. By screwing the adjusting bolt 218 inwardly, the tension on the springs 210 is increased and the pressure of the main broom 44 on the surface to be swept is decreased. Similarly, by screwing the adjusting bolt 218 outwardly, the rectangular member 212 moves toward the rear relative to the plate 206 so that the tension on the springs 210 is decreased and the pressure of the broom on the surface is increased. In practice, the springs 2110 need adjustment very seldom and are primarily used to compensate for wear of the bristles 220 of the broom 44.

More frequent and finer adjustment of the pressure of the main broom 44 on the surface can be effected by means of a single adjusting spring 222. One end of the spring 222 is attached to a connecting pin 224 at the upper end of an adjusting spring arm 226 which is rotatably mounted on the lift shaft 200 but has a dog 227 which engages an extension of the bolt 214 when the arm 226 is pulled rearwardly by the spring 222. Tension on the spring 222 is varied by an adjusting lever 228 which is suitably pivoted to a pin 230 supported by a portion of the sweeper frame 22. The lever 228 is moved forwardly and rearwardly by a threaded adjusting rod 232 which engages an intermediate portion of the lever and is threadedly engaged in a bracket 234, in turn, supported by a portion of the frame 22.

When the rod 232 is screwed inwardly with respect to the plate 234, the lever 228 is moved rearwardly thereby increasing the tension on the spring 222. The spring 222 urges the adjusting plate 226 rearwardly causing the dog 227 to engage the bolt 214 and to urge the plate 206 rearwardly. Thus, increasing the tension on the spring 222 decreases the pressure of the main broom 44 on the surface. Similarly, when the adjusting rod 232 is screwed outwardly, the adjusting lever 228 is moved forwardly, thereby decreasing the tension on the spring 222. The arm 226 also moves forwardly and enables the plate 206 to move forwardly, thereby increasing the pressure of the broom 44. The spring 222 and the adjusting rod 232 thus provide easy and quick pressure adjustment and are especially useful for changing broom pressure for particular surfaces to be swept. It may be noted that the tension of the spring 222 has no effect on the pressure of the broom 44 once it is released sufficiently that the adjusting spring arm 226 moves forwardly 6 enough to cause the dog 227 to separate from the bolt 214. This will occur when the lift plate 206 is raised sufliciently that the spring 222 becomes slack.

The cam plate 178 and the triangular lift plate 206 are connected by means of a telescoping link 236 which comprises a small rod 238 (FIG. 5) pivotally attached by a pin 240 to a rear, lower end of the cam plate 178 and a larger hollow tube 242 which is pivotally attached to the forward corner of the triangular plate 206 by a pin 244. When it is desired to raise the front flap 42 during the regular sweeping operation, the front flap handle 182 can be moved upwardly to push the roller arm 174 downwardly and to move the cable arm 166 rearwardly, thereby pulling on the cable 156 and raising the flap 42. When this action occurs, the rear end of the cam plate 178 moves forwardly and downwardly which simply causes the small rod 238 to move partly out of the tube 242, thereby having no affect on the plate 206 or the main broom 44. Thus, the handle 182 can be raised and lowered to raise and lower the front flap 42 in the manner heretofore described, without having any affect on the operation of the main broom 44.

When the sweeping operation is finished, the main broom 44 and the front flap 42 should both be raised in order to reduce wear and tear thereon. To accomplish this, the handle 182 is pushed downwardly whereby the plate 178 then moves in a clockwise direction and the rear end thereof moves upwardly and toward the rear. This pushes the linkage 236 rearwardly and forces the lift plate 206 in a counterclockwise direction, thereby raising the broom 44 in the manner heretofore described. The downward movement of the handle 182 is continued until the linkage 236 reaches an over-center position with the pivot pins 240 and 244 being above a line through the lift plate pivot 180 for the cam plate 178 and the shaft 200 which constitutes the pivot for the lift plate 206. The lift plate 206 and the cam plate 178 then remain in those positions until the handle 182 is again pulled upwardly.

From the above discussion, it will be seen that the broom and flap controls have many advantages. More or less permanent adjustment of the broom 44 can be controlled by means of the springs 210 and the adjusting bolt 218 whereas more frequent and finer adjustment of the pressure can be attained through the single spring 222 and the adjusting rod 232. Temporary increased or decreased pressure on the broom 44 can be easily effected by the operator simply by pushing downwardly or pulling upwardly on the main broom handle 208. Further, the front flap 42 can be raised or lowered by raising and lowering the front flap handle 182 whereas more permanent raising of both the flap 42 and the main broom 44 can be effected simply by pressing downwardly on the handle 182 until the linkage 236 is in an over-center position.

Various modifications of the above-described embodiment of the invention Will be apparent to those skilled in the art and it is to be understood that such modifications can be made without departing from the scope of the invention, if within the spirit and tenor of the accompanying claims.

What I claim is:

1. A power sweeper for sweeping a large surface comprising, in combination, a main frame, a pair of rear wheels rotatably mounted on said frame, a steerable front wheel supporting a front portion of said frame, an operators seat on said frame, a main broom rotatably held by said frame, a front flap in front of said main broom and located generally perpendicularly to the direction of movement of said sweeper, said front flap including first and second strips and a front flap supporting bar, said first strip being flexible with the width thereof being greater than the distance between said supporting bar and the surface, said second strip being relatively stiff with the Width thereof being less than the distance between said supporting bar and the surface, said second strip being mounted in front of said first strip with upper edges of both of said strips being attached to said front flap supporting bar, said front flap supporting bar being rotatably mounted at its ends on said frame, a third, stationary, backing strip, means for supporting said stationary strip on said frame between said front flap and said main broom, a front flap cable wound around an end of said front flap supporting bar, a cable spring connected between an end of said cable and said frame, a cable arm attached to the other end of said cable, a cable shaft rotably held by said frame and aifixed to said cable arm to turn said cable arm when said cable shaft is turned, a roller arm fixed to said cable shaft at a point spaced from said cable arm, a roller mounted on said arm, a cam plate pivotally supported by said frame in engagement with said roller, and a front flap handle attached to said cam plate to pivot said cam plate, said cam plate being shaped to force said roller and said roller arm downwardly whether said cam plate handle is moved upwardly or downwardly, downward movement of said roller arm causing said cable to rotate said front flap supporting bar and to raise said first and second strips in an arcuate path.

2. A power sweeper for sweeping a large surface comprising, in combination, a main frame, a pair of rear wheels rotatably mounted on said frame, a steerable front wheel supporting a front portion of said frame, an operators seat on said frame, a generally horizontally-disposed, driven shaft rotatably supported by said main frame, a main broom, an axle for said main broom, a main broom axle-supporting member, one end of which is rotatably connected to an end of said main broom axle, and the other end of which is rotatably mounted on said driven shaft, a main broom driven sprocket affixed to the other end of said main broom axle, a main broom drive sprocket aflixed to said driven shaft, a main broom chain connecting said main broom sprockets, a chain guard, an end of which is rotatably mounted on the sprocket end of said main broom axle and the other end of which is rotatably mounted on said driven shaft, a first main broom lift rod attached to said main broom axle-supporting member and extending upwardly, a first main broom lift arm pivotally attached to said first main broom rod, a main broom lift shaft rotatably supported by said frame, a second main broom lift rod attached to said chain guard and extending upwardly, a second main broom lift arm, said first and said second main broom arms being affixed to said main broom shaft for rotation therewith, a main broom lift plate aflixed to an intermediate portion of said main broom shaft, a main broom handle attached to said main broom plate for moving said main broom plate and turning said main broom shaft to turn said first and second main broom arms to raise and lower said main broom member and said chain guard, thereby to decrease and increase the pressure of said main broom on the surface, a plurality of pressure springs connected to said frame, means adjustably connecting said pressure springs to said main broomplate, an adjusting spring arm rotatably supported on said main broom lift shaft, means on said adjusting spring arm for engaging said main broom plate when said adjusting spring arm is moved rea'rwardly, an adjusting spring, and adjusting means supported by said frame and connected to one end of said adjusting spring, the other end of said adjusting spring being connected to said adjusting spring arm.

3. A power sweeper for sweeping a large surface comprising, incombination, a main frame, a pair of rear wheels rotatably mounted on said frame, a steerable front wheel supporting a front portion of said frame, an operators seat on said frame, a main broom rotatably held by said frame, a front flap in front of said main broom and located generally perpendicularly to the direction of movement of said sweeper, said front flap including at least one flexible strip, and a front flap supporting bar affixed to an upper edge of said strip, the width of said strip being greater than the distance between said supporting bar and the surface, said front flap supporting bar being rotatably mounted at its ends on said frame, a front flap cable wound around an end of said front flap supporting bar, a cable spring connected between an end of said cable and said frame, a cable arm attached to the other end of said cable, a cable shaft rotatably held by said frame and afiixed to said cable arm to turn said cable arm when said cable shaft is turned, an additional arm afiixed to said cable shaft at a point spaced from said cable arm, a cam plate pivotally supported by said frame in engagement with said additional arm, a front flap handle attached to said cam plate to pivot said cam plate, said cam plate being shaped to force said additional arm downwardly whether said cam plate handle moves upwardly or downwardly, downward movement of said additional arm causing said cable to rotate said front flap supporting bar and to raise said strip in an arcuate path, an axle for said main broom, means pivotally supporting said axle in' a generally horizontal position and at varying distances above the surface, main broom lift rod means attached to said main broom supporting means and extending upwardly therefrom; main broom lift arm means pivotally attached to said main broom lift rod means, a main broom lift shaft rotatably supported by said frame and afiixed to said main broomlift arm means for pivoting the same, a main broom lift plate affixed to an intermediate portion of said main broom shaft, a main broom handle attached to said main broom plate for moving said main broom plate and for turning said main broom shaft to turn said main broom arm means to raise and lower said main broom, thereby to decrease and increase pressure of said main broom on the surface, and a telescoping link connecting said main broom plate and said cam plate, whereby said cam plate can be moved in one direction without moving said main broom plate, in order to raise said front flap only, and said cam plate can be moved in the other direction to move said main broom plate to raise both said front flap and said main broom, said link being movable to an over-center position to hold said main broom and said front flap upwardly until said front flap handle is released.

4. A power sweeper for sweeping a large surface comprising, in combination, a main frame, wheel means ro tatably mounted on said frame for driving and steering said sweeper, a main broom rotatably held by said frame, a front flap in front of said main broom and located generally perpendicular to the direction of movement of said sweeper, said front flap including at least one flexible strip, and a front flap supporting bar affixed to an upper edge of said strip, said front flap supporting bar being rotatably mounted at its ends on said frame, a front flap cable wound around a portion of said supporting bar and being capable of rotating said supporting bar when said cable is pulled, a cam plate pivotally mounted on said frame, a front flap handle attached to said cam plate to pivot said cam plate, means connecting said cam plate to said front fiap cable to pull said cable when said cam plate is moved in either of two opposite directions by said front flap handle, an axle for said main broom, means pivotally supporting said axle in a generally hori zontal position and at varying distances above the surface, a main broom shaft rotatably supported on said frame, means connecting said main broom shaft and said pivotal-supporting means to raise and lower said main broom when said main broom shaft is rotated, a main broom lift plate aflixed to said main broom shaft, a main broom handle attached to said main broom plate for pivoting said main broom plate in one direction to raise said main broom, and a telescoping link connecting said main broom plate and said cam plate whereby said cam plate can be pivotally moved in one direction without moving said main broom plate, in order to raise said front flap only, and said cam plate can be pivotally moved in the other direction to pivotally move said main broom plate to raise both said front flap and said main broom.

5. A power sweeper for sweeping a large surface comprising, in combination, a main frame, a pair of rear wheels rotatably mounted on said frame, a front wheel supporting a front portion of said frame, an operators seat on said frame, a main broom rotatably held by said frame, a front flap in front of said main broom and located generally perpendicularly to the direction of movement of said sweeper, said front flap including first and second strips and a front flap supporting bar, said first strip being flexible with the width thereof being greater than the distance between said supporting bar and the surface, said second strip being stiffer than said first strip with the width thereof being less than the distance between said supporting bar and the surface, upper edges of both of said strips being attached to said front flap supporting bar, said front flap supporting bar being rotatably mounted at its ends on said frame, a third, stationary, backing strip, means for supporting said stationary strip on said frame between said front flap and said main broom, a front flap cable wound around an end of said front flap supporting bar, means operable from a location near the operators seat for pulling on said cable to rotate said supporting bar to move said flap in an arcuate path, and spring means associated with said cable to urge said supporting bar toward its original position.

6. A power sweeper for sweeping a large surface comprising, a main frame, wheels rotatably mounted on said frame for driving and. steering said sweeper, a main broom rotatably held by said frame, a front flap in front of said main broom and located generally perpendicularly to the direction of movement of said sweeper, said front flap including a flexible strip and a front flap supporting bar, said strip being wider than the distance between said supporting bar and the surface, said supporting bar being rotatably mounted at its ends on said frame with an upper edge of said strip being attached to said supporting bar, and means connected to said supporting bar for rotating said supporting bar to raise and lower said strip in an arcuate path with the free end of said strip moved forwardly as said strip is raised.

7. A power sweeper for sweeping a large surface comprising, in combination, a main frame, a pair of rear wheels rotatably mounted on said frame, a front wheel mounted on a front portion of said frame, an operators seat on said frame, a generally horizontally-disposed, driven shaft rotatably supported by said main frame, a main broom, an axle for said main broom, a main broom axle supporting member, one end of which is rotatably connected to an end of said main broom axle, and the other end of which is rotatably mounted on said driven shaft, sprocket means attached to the other end of said main broom axle and to said driven shaft for driving said main broom, guard means around said sprocket means, an end of said guard means being rotatably connected to the sprocket end of said main broom axle and the other end being rotatably mounted on said driven shaft, lift rod attached to said member and said guard means and extending upwardly therefrom, lift arms pivotally attached to said lift rods, a main broom lift shaft rotatably supported by said frame and afiixed to said main broom arms to rotate said arms, a main broom lift plate attached to an intermediate portion of said main broom lift shaft, a main broom handle attached to said main broom plate for moving said main broom plate and turning said main broom lift shaft to turn said main broom arms in order to raise and lower said main broom member and said guard means, thereby to decrease and increase the pressure of said main broom on the surface, first pressure spring means connected to said frame and to said lift plate to urge said lift plate in a direction to decrease the pressure of said broom on the surface, an adjusting spring arm rotatably supported on said main broom shaft, means on said adjusting spring arm for contacting said lift plate when said adjusting spring arm is moved rearwardly, an adjusting spring, and adjusting means supported by said frame and connected. to one end of said adjusting spring, the other end of said adjusting spring being connected to said adjusting spring arm whereby tension on said adjusting spring can be varied to change the position of said adjusting spring arm to change the pressure of said main broom on said surface.

8. A power sweeper for sweeping a surface comprising, in combination, a main frame, wheel means rotatably mounted on said frame to support and drive said sweeper, an operators seat on said frame, a generally horizontally-disposed driven shaft rotatably supported by said main frame, a main broom, an axle for said main broom, a main broom axle supporting member pivotally supporting an end of said. main broom axle on said driven shaft, means at the other end of said main broom axle for driving the same and for pivotally supporting the driven end of said main broom axle around said driven shaft, lift means attached to said axle-supporting member and said axle-supporting means and extending upwardly therefrom, a main broom lift shaft rotatably supported by said frame and attached to said lift means, a main broom lift plate afiixed to an intermediate portion of said main broom lift shaft, a main broom handle attached to said main broom plate for moving said main broom and said main broom shaft to raise and lower said. main broom to decrease and increase the pressure of said main broom on the surface and to apply additional pressure on the surface exceeding the weight of the broom, linkage means associated with said main broom handle for holding said main broom in an upper position when said handle is moved to a predetermined position, and spring means as sociated with said lift plate for urging said lift plate in a direction to decrease the amount of pressure of said main broom on the surface.

References Cited by the Examiner UNITED STATES PATENTS 468,458 2/ 1892 Slawson 1584 529,132 11/1894 Mueller 1583 876,727 1/1908 Pevey 1583 X 1,374,933 4/1921 Lund 1583 1,797,185 3/1931 Allen 1584 2,055,011 9/1936 Hough 1582 2,156,065 4/1939 Royer 1582 FOREIGN PATENTS 2,867 1/ 1889 Great Britain.

CHARLES A. WILLMUTH, Primary Examiner.

WALTER A. SCHEEL, Examiner. 

6. A POWER SWEEPER FOR SWEEPING A LARGE SURFACE COMPRISING, A MAIN FRAME, WHEELS ROTATABLY MOUNTED ON SAID FRAME FOR DRIVING SAID STEERING SAID SWEEPER, A MAIN BROOM ROTATABLY HELD BY SAID FRAME, A FRONT FLAP IN FRONT OF SAID MAIN BROOM AND LOCATED GENERALLY PERPENDICULARLY TO THE DIRECTION OF MOVEMENT OF SAID SWEEPER, SAID FRONT FLAP INCLUDING A FLEXIBLE STRIP AND A FRONT FLAP SUPPORTING BAR, SAID STRIP BEING WIDER THAN THE DISTANCE BETWEEN SAID SUPPORTING BAR AND THE SURFACE, SAID SUPPORTING BAR BEING ROTATABLY MOUNTED AT ITS ENDS ON SAID FRAME WITH AN UPPER EDGE OF SAID STRIP BEING ATTACHED TO SAID SUPPORTING BAR, AND MEANS CONNECTED TO SAID SUPPORTING BAR FOR ROTATING SAID SUPPORTING BAR TO RAISE AND LOWER SAID STRIP IN AN ARCUATE PATH WITH THE FREE END OF SAID STRIP MOVED FORWARDLY AS SAID STRIP IS RAISED 